Examples of Weed Seed Production Per Plant
Learn about the “weed seed bank” and how the “never let ’em seed” rule can help maintain a weed-free garden.
By Robert Norris, Ph.D., Fellow of the Weed Science Society of America
Most people don’t realize that a weed can produce literally thousands — or even millions — of seeds per plant. The chart shows the number of seeds coming from single weed plants. Learn more about the “weed seed bank” in Never Let ’Em Seed.
| Weed Name | Weeds Per Plant | Where the Plant Was Located |
| Barnyardgrass, Echinochloa crus-galli | 750,000 | Davis, CA |
| Purslane, Portulaca oleracea | > 2,000,000 | Davis, CA |
| Black nightshade, Solanum ptycanthum | >800,000 | Rosemount, MN |
| Puncturevine, Tribulus terrestris | >100,000 | Pullman, WA |
| Powell amaranth, Amaranthus powellii | 268,000 | Freeville, NY |
| Shepherd’s purse, Capsella bursa-pastoris | 40,000 | Sheffield, UK |
| Chickweed, Stellaria media | 25,000 | Rothamsted, UK |
Data collected by various researchers around the globe.
